The present invention relates to improved cleaning compositions which find particular use in hard surface cleaning applications.
Cleaning compositions are commercially important products and enjoy a wide field of utility in assisting in the removal of dirt and grime from surfaces, especially those characterized as useful for cleaning “hard surfaces”. Hard surfaces include those which are frequently encountered in lavatories, for example lavatory fixtures such as toilets, shower stalls, bathtubs, bidets, sinks, etc., as well as countertops, walls, floors, etc. In such lavatory environments various forms of undesirable residues are known to form including hard water stains as well as “soap scum stains”. Hard water stains are mineral stains caused by the deposition of salts, such as calcium or magnesium salts, frequently present in hard water. Soap scum stains are residues of fatty acid soaps, such as soaps which are based on alkaline salts of low fatty acids. These fatty acids are known to precipitate in hard water due to the presence of metal salts therein leaving an undesirable residue upon such surfaces.
Various formulations in compositions of cleaning agents have been produced, and it is generally known to the art which cleaning agents are generally suited for one type of stain but not necessarily for both classes of stains. For example, it is known to the art that highly acidic cleaning agents comprising strong acids, such as hydrochloric acids, are useful in the removal of hard water stains. However, the presence of strong acids is known to be an irritant to the skin and further has the potential of toxicological danger. Other classes of cleaning compositions and formulations are known to be useful upon soap scum stains. However, generally such compositions comprise an organic and/or inorganic acid, one or more synthetic detergents from commonly recognized classes such as those described in U.S. Pat. No. 5,061,393; U.S. Pat. No. 5,008,030; U.S. Pat. No. 4,759,867; U.S. Pat. No. 5,192,460; U.S. Pat. No. 5,039,441. Generally, the compositions described in these patents are claimed to be effective in the removal of soap scum stains from such hard surfaces and may find further limited use in other classes of stains.
However, the formulations of most of the compositions within the aforementioned patents generally have relatively high amounts of acids (organic and/or inorganic), which raises toxicological concerns, and further none of the above patents provides any disinfecting properties.
Compositions are known to the art which do provide disinfection and sanitization through the use of certain classes of anionic surfactants coupled with an acidic component, such as that described in U.S. Pat. No. 5,143,720. However, the compositions in this U.S. patent would not be expected nor are believed to provide any significant cleaning benefit and thus would not be particularly effective in the removal of residues, particularly hard water stains and soap scum stains.
International Patent Publication WO 97/15649 describes a hard surface composition having an acidic pH. The composition provides good removal of soap scum stains, and features low levels of irritability to the user.